New Rims in a Year ?

[Lazy-Commuter]

Having done 1600 or so miles since buying my Giant MTB in July 2007, mostly commuting, I thought I'd put it in the LBS for a bit of a service before the Winter. I knew the brake blocks were pretty worn so asked them to have a look / replace them, but they are saying that the wheel rims are shot and need replacing.

Surely I can't have trashed the rims in a year? 1600 miles isn't that far, is it? My ride to work is a (tiny) bit off road, but mostly on road. I'm going to have a bit of a chat tomorrow about it with them, and a look, not that I particularly know what I'm looking at. So thought I'd ask for some opinions here: should this be a warranty thing, do you think?

Any comments appreciated.

 

[gbb]

One of my road bikes had rims that showed definate wear..despite seemingly light use with the brakes.
Riding in the winter tends to get all sorts of debris into the pads....that was what was damaging mine. At its worst, you could hear them grinding. Thats when i decided to investigate (a bit late) and i was amazed at the crud and stonechips embedded into the pads.

 

[fossyant]

Look after the pads... I'm on my 3rd set of pads since August last year...if you haven't changed or adjusted your pads, then your rims will be goosed....SORRY !

I have about 3000 miles on 3 sets, so 1000 each set of pads, but that includes winter and wet - any signs of wear, replace - or it's new wheels very quickly. That excludes Road bike use - just the commuter MTB !

You need to check for regular re-adjustment, especially when wet, like this summer...... as the pads wear fast....then if badly adjusted, etc...the rims will follow...

Changing worn pads stops the build up of rim rubbish (alloy particles) in the pads - new pads, less alloy to scrub the rims....

Other issue - do you wash the bike often...if not..well that's half the problem.

 

[andrew_s]

1600 miles to dead(ish) rims is entirely possible, but is sufficiently soon that action is required.

The most likely reason is that bits of grit etc are getting embedded in the brake blocks so that every time you use the brakes the grit is grinding away the aluminium of the rim. Some brake blocks are a lot more prone to getting stuff in them than others, so I'd suggest changing blocks. There isn't much point in picking out the stuff in your existing blocks as they have already shown themselves to be poor.
I've found that Shimano blocks are poor and Koolstop are good, in respect to rim wear.

If you want to ignore the bike shop and keep using your existing rims, you should pressure test them at intervals by inflating them to 50% above the maximum recommended pressure stated on the side of the tyre and leaving them overnight. They should be OK for a while if they haven't gone bang, and there hasn't been any visible deformation in the rim sidewalls (look at them beforehand).

 

[Lazy-Commuter]

Thanks for all the replies. I do clean the bike thoroughly every few weeks, but haven't been diong it every week or anything like that. It hasn't had a lot of winter / wet / muddy use: it was bought originally to keep up with the kids once they became (reasonably) competent on their bikes .. too much like hard work running around behind them!! So it's been mostly family trails 'til I hit on the idea of using it to get to work. There's a bit of mud on the way to work, but not a lot.

I am planning to use it through this winter so guess I'd best keep a better eye on the pads: this was the first set. Being OE, they're probably Shimano. I've done adjustment things to the brakes, although mostly cable tension admittedly plus the occasional look at the blocks. They were still stopping nicely, not squeaking or juddering and still seemed to have plenty of meat on them so I left well alone .. bad idea I guess.

Presumably it's going to want a wash round at least every weekend with winter use, plus some careful TLC on the brakes.

I trust the LBS - they're good guys - so will get it done. I was just a bit surprised the rims had gone so quick (well, seemed like to me) and wanted to get some impartial thoughts on the matter.

Cheers
L-C

 

[summerdays]

I had new rims after about 16 months ... but then when I first got the bike I didn't understand that I needed to clean the rims of that grey gunk. It also depends on how much you use the brakes - if there are loads of hills you tend to use the brakes more.

 

[fossyant]

I wash the bike after wet rides (which is often) - but at least get the gunk off the rims

 

[domtyler]

The difference between how often I'd like to wash my bikes and how often I actually wash them is fairly substantial. What I do do though is to take a baby wipe and wipe the rims clean at least every week. In fact one baby wipe and a couple of sheets of kitchen roll can bring a grimy bike back to a surprisingly respectable state.

 

[Lazy-Commuter]

Thanks All

Some more food for thought there, thanks everyone.

I don't have very much in the way of hills on the way to / from work, the biggest one is a drop of around 60m in the space of half a mile or so just before I get home. It's down a narrow windy lane, mostly quiet but I tend to be cautious 'cos you do get cars going up it.

So that tends to be a "brake quite hard just before the corners and then let speed pick backup, repeat" cycle for a bit. And I'm quite heavy (especially for a shortass like what I am ) so that probably does put a bit of pressure on the brakes.

Worse than that, thinking about it, this is just after the muddiest bit of my journey so I will quite often be doing this section with a nice muddy grinding paste on the rims. Maybe I'll take some baby wipes with me and give it a wipe before coming down the hill. Presumably they don't leave a residue Dom?

Any other top tips for rim cleaning? (Sounds like something you'd use down the toilet!)

 

[RedBike]

Wearing out a set of rims in a year isn't uncommon but it generally takes either a heck of a lot more then 2k miles or a lot of muddy / gritty off-road miles.

One set of brake blocks lasting a year? Errrm, I can easily wear out a set in one ride off-road; and they generally don't last the month on the road if its wet.

I can't see how a set of brake blocks could last as long as a rim.

Either the pads were completely the wrong compound, (which would explain why your rim has worn so quickly but your pads haven't) or you had gravel embeded in the pads.

The gravel would of left big gouges in the rim and made a noise. You would of noticed this?